Arc extinguishing device



Aug. 11, 1931. A, M, JACKSON A 1,817,984

` ARC EXTFNGUISHING DEVICE med Deo. so, 19726 zksneets-sneet 1 il' cliff@ ef', l

Ma/f Y Aug. 1l, 1931. lA. M. JACKSON 1,817,984

' Anc EXTINGUISHING DEVICE Filed Dec. 30, 1926 2 Sheets-Sheet 2 Patented Aug. ll, 1931 ,y UNITED STATES PATENT OFFICE ALEXANDER M. JACKSON, OF EVANSTON, ILLINOIS, ASSIGNOR T0 LOCXE INSULATOB OOEPOBATION, OF BALTIMORE, MARYLAND, A CORPORATION 0F MARYLAND anc :EXTINGUISHING DEVICE Application led December 30, 1926. Serial No. 157,911.

This invention relates. to means for extinguishing electric arcs, and-more particularly to an arc`extinguishing device adapted for use with insulator strings employed on high tension lines, and stacks of insulators erlriiployed on high voltage switches, and the li e.

As is known, arcs following Hash-overs of high voltages from conductors to ground frequently occur, in spite of all means that are taken to prevent them. These arcs following flash-overs to ground cause interruption to service, and damage to material.y Such flash-overs occur in high tension transmission lines when abnormal or excessively high potential between the conductor and ground is relieved by the breaking down of the air between spaced arcing contacts, one ofI which is grounded. While this serves to relieve the excessively high tension on the line, serious interruption to transmission and damage apparatus is apt to result if the arc following the Hash-over or spill is sustained for an a reciable len h of time, as not infrequent y appens, an it may be necessary to reduce or in extreme cases take the voltage o of the line to extinguish the arc. I have found that this objection can be overcome by providing means for immediately extinguishing the arc after formation thereof, this' means being automatic in its operation and rendered active by the arc itself. While I have illustrated and described my invention as used in connection with the protective apparatus of a transmission line, I do not intend in any way to limit myself to this one particular use, as my invention can be readily appliedl in various manners and with various apparatuses. It will be understood, therefore, that I contemplate using my invention in numerous other ways than the particular manner hereinillustrated and described in detail.

One of the main objects of my invention is to provide a device of simple and inexpensive construction which can be readily applied to an arcing horn of standard construction. A further object .is to provide a device of this character which will be effective in extinguishing a number of successive arcs without the necessity of renewal or repairing of the outwardly radially device.- Another object is`to provide an extinguishing device which can be employed by being mounted upon one of the arcing terminals or can be disposed between .the terminals and in the path of the arc. Further objects will appear from the detailed description.

In the drawings Figure l is an elevation of a string of insulators `and associated means supporting the transmission cable or conductor, showin arc extinguishing devices applied in accor ance with my invention;

Figure 2 is an enlarged detail view of the terminal portion of one of the horns and the extinguishing device, the latter being shown 1n section;

Figure 3 is a central longitudinal section through one form of extinguishing device;

Figure 4 is a similar view through a modified form of device; 1

, Figurel 5 is a view similar to Figure 3 showing a different form of arc extinguishing material;

Figure 6 is a central longitudinal section through another modilied form of the device; A

Figure 7 is an elevation of another modied form showing the manner of using an arc extinguishing fuse;

Figure 8 is an elevation showing yet another form of the invention.

My invention is illustrated'by way of example, as used in connection with a high tension conductor 1 which is supported by suitable securing and clamping means 2 from the lower end of an insulating'structure 3 y suspended at its u per end from a sup orting arm 4 extending rom a tower (not s own), such as is commonly used in supporting high tension transmission lines. A yoke l5 is mounted at the upper end of the structure 3 and electrically connected to arm 4 so as to be grounded thereby tol the tower, in a known manner. The insulating structure 3 is formed of a string of units or insulators o'f known construction which are loosely secured together in a known manner. The oke 5 is formed to provide two horns 6 whic extend beyond the uppermost insulator of the string and are inclined downwardly, these members forming the present arcing horn used in structures of this sort. An arcing ring 7 is supported at the lower end of the string of insulators by arms 8 extending from the clamping and securing means 2. Instead of a ring 7, arcing horns may be employed. Preferably, though not necessarily, this ring is bent to provide, in effect, two arcing terminals 9 which are disposed in alignment with the terminal portion 6a of the arms or horns 6. The structure so far described is of known construction and I do not claim such construction as my invention except in so far as it cooperates with the means to be described for extinguishing arcs.

A container 10 of electrical insulated material is closed at its upper end by a cap or closure member 11 of suitable conducting material, this closure member being provided with an upwardly extending ange 12 which is secured by rivets 13, or in any other suitable or preferred manner, to the arcing terminal 6a of horn 6. Obviously, the specific details of the parts of the closure or container may be varied without departure from my invention. A fusible conductor 14 is secured at its upper end in the closure member 11- so as to be electrically connected thereto and to horn 6, and extends through a closure member or disc 15 suitably sealed in the lower end of container 10. This disc 15 may be of any suitable or preferred material but, in the present instance, it is preferably of lead or other readily fusible conducting material. Conductor 14 extends through the disc which fits tightly about the conductor to form a tight closure, and projects beyond the lower or inner end of the container an appreciable distance to provide an element 14a to which the arc will strike when it is formed. Preferably, a suitable indicating element, such as a disc 16 of white paper, is mounted upon the outer face of the closure member 15 so as to be destroyed or discolored when the 'conductor 14 is fused by the are. The container 10 is filled with a suitable arc extinguishing material 17. This material may be in the form of a solid, of which there are several suitable for this purpose, formed of a gas, a liquid, or a suitable absorbent material saturated with an arc extinguishing liquid. The material illustrated in Figure 2 and indicated at 17 consists of a suitable absorbent such as cotton waste, which is saturated with carbon tetra-chloride which possesses high dielectric strength and is very efiicient inquenching arcs.

With the arc extinguishing device mounted upon the terminals of the horns 6, the arc will strike to elements 14a of conductor 14 when abnormally high tension is developed suiicient to break down the insulating air gap between the arcing terminals. 'Ihe conductor 14 is preferably of such size and made of such material that it is not fused by the heat of the current passing through it, but is fused by the contact of the arc with the end of the conductor, at which point intensely high temperatures are developed. As the conductor 14 is eaten away or fused and destroyed by the arc, the arc enters the mass of the material 17 so as to be surrounded thereby, the intense heat developed in this material by the arc resulting in the formation of vapors of carbon tetrachloride, or such other extinguishing liquid, and these vapors serve to quickly extinguish the arc. In the event that the arc should reform after being extinguished in this manner, which is very exceptional, the remaining arc extinguishing agent in the material 17 would serve to extinguish this second arc. The arc extinguishing agent remaining in the filling 17 would also serve to extinguish a second arc which might be formed between the terminals at any time after extinguishing of the first arc, if this second arc were formed before the arc extinguishing agent had been dried out, evaporated or otherwise dissipated or released from the filling 17. The device is, therefore, adapted for quenching two or more arcs which might form successively even over a comparatively long period of time, under unusual conditions.

Instead of being disposed in a fibrous absorbent filling, the arc extinguishing agent might be absorbed in or combined with other material to form a fairly stable or permanent substance. For example, I contemplate solidifying the active agent by combination with other material.

In Figure 4 I have illustrated a form of extinguishing device in which a plurality of containers 10a, 10b, and 100 are mounted upon conductor 14?) similar to but longer than conductor 14. Container 10a is constructed similarly to container 10 and containers 10?) and 10c are closed at their upper ends by fusible closure members 10d and at their lower ends by closure discs or members 15 of lead or other suitable fusible material, paper indicating disc 16 being mounted on the outer faces of discs 15. Each of the containers 10a, 10b, and 10c are provided with a filling of cotton waste, or other suitable material, saturated with arc extinguishing agent, or other suitable filling, this filling being indicated at 17. By this arrangement I provide a series or magazine of arc extinguishing devices each of lwhich is eifectually sealed so as to prevent loss or eva oration of the arc extinguishing agent. This evice-is particularly well adapted for points at which arcs are apt to form more than once. When an arc is formed it will strike the projecting portion 14o of conductor 14?; and, as the conductor is eaten away, the arc will enter the lowermost container 10c and will be extinguished by the arc extinguishing agent released from this container. If a second arc developes at a later period, and after escape, evaporation, or dissipation of the ex'- tinguishing material in the lowermost container 10c, this second arc will melt away the conductor 146 until it enters the second container 10b where it will be extinguished. In like manner, a third arc which forms at `a later period will be extinguished in the container 10a. It will be also understood that two or more succeeding arcs may be extinguished in anyone of the containers, if these arcs occur wlthin short periods of time of each other, as explained in connection with the form of device illustrated in Figure 2.

The form of device illustrated in Figure 3 is similar to that illustrated in Figure 2 with the exception that the body 10 is appreciably longer, the conductor 14 being correspondingly increased in length to extend the fuli length of the body 10 and provide the proecting element 14". The form illustrated 1n igure 5'is similar to that illustrated in Figure 3 with the exception that the arc extinguishing material or filler 17a is illustrated as a solid. Any one of several solids known in the art may be employed for this purpose. Preferably, I employ carbon tetrachlorlde absorbed in a solid or semi-solid and adapted to be released or vaporized preferably by the heat of the arc.

The form of the device illustrated in Figure 6 is similar to that illustrated in Figure 3 with the exception that the fusible conductor 14' is replaced by an element which is fused by the heat of the current, and a liquid arc extinguishing material 17 bis em loyed. The liquid used in this form is pre erably carbon tetra-chloride, or the like, as this possesses very high dielectric strength and acts to very quickly extinguish an arc develo ed in the liquid. 'In this form I provide al use member 18 provided at its ends with enlarged elements or heads 18a and 18b which pass through and are secured in the lclosure members or discs 15 and 11, respectively. The terminal member 18a is not fused by the heat of the arc so as to cause the arc to enter the container 10', as'in previous forms, but the element 18 is melted or fused by the heat of the current passing therethrough, thus forming a gap within the container, and the arc in passing across this gap is immediately extinguished by the liquid agent within the container. This device thus forms a true fuse, the fusible element or link of which is surrounded by the arc extinguishing liquid.

In the modification illustrated in Figure 7, I employ a fuse 19 mounted in cli s 20. One of these clips is secured about t e end portion of horn 6, the other clip being secured about a. tapered arcing point 21 secured at the lower end of an insulating element 22 which is secured to the outer or lower end of horn 6. The fuse 19 is preferably a Schweitzer and Conrad fuse of the type illustrated in the d patent to E. Q. Schweitzer and N. J. Conrad,

No..1,135,548, issued April 13, 1915. This fuse includes a tube 23 of glass or other suitable insulating material provided at its ends with terminals (not shown). A fusible element or link is secured at one end to one of the caps or ferrules and-is connected at its other end to a tension spring 24, the other end of which is secured to the other end of the fuse structure. A suitable iexible conductor is associated with the spring for conducting the current to the fusible element without subjecting the spring to undesirableheating effect. The tube 23 is filled with carbon tetrachloride, or similar extinguishing liquid, and when the fusible element or link is fused by the heat of the current passing through the same, the spring retracts so as to separate the arcing terminals drawing the arc in the liquid which acts to quickly yextinguish it. Under certain conditions this modified form of my invention is very satisfactory though nor'- mally I prefer to use the form previously described. The upper cap of said fuse may be blown clear of the mounting.

In Figure 8 I have illustrated a further modification of my invention in which I provide a supplemental yoke 25 secured about the middle one of the string 3 of insulators. This yoke is provided at each end above and below with an arc extinguishing device 26 similar to that illustrated in Figure 6, this device being secured to the ends of the yoke by means of clips 27, or in any other suitable or preferred manner. Preferably the extinguishing device 26 faces both ways; that is, it has a common central body and a fusible conductor exposed at each end. The devices 26 are disposed between the arcin terminals of the ring 7 and the yoke 5 and 1n the path of the arc developed between these terminals. If an arc is formed it will strike to the rojectlng portion 18a of the element 18 an the current flow will immediately meltthe fusible element 18, the arc being extinguished Within the container 10. This form may be applied to present installations for su porting high tension conductors under con itions where it is not convenient or practical to apply extinguishin devices directly to the ends of the horns 6 o the yoke 5.

As will be clear from the above, numerous changes in construction and arrangement of part-s of the invention may be resorted .to without departing from the field and scope of the same, and I intend to include all such variations, as fall within the scope of the appended claims, in this application in which the preferred forms only of my invention are disclosed..

What I claim is 1. Means for-extinguishing an arc which may occur between spaced terminals comprising a container of insulatin material secured at its outer end to one of e terminals, a fusible closure at the inner end of the container, a fusible conductor extending through the container to said closure and connected to the arcing terminal to which the container is secured and projecting through and beyond the other end of the latter, and arc extinguishing material within the container surrounding said conductor.

2. Means for extinguishing an arc which may occur between spaced terminals comprising acontainer of insulating material, a closure member of conducting material at the outer end ofthe container, said closure member being secured to one of the terminal members, a closure member at the inner end of the container, a fusible conductor connected to the outer closure member and extending through the casing through and beyond the inner closure member, said inner closure member being of conducting material, and arc extinguishing material within the container surrounding said conductor.

3. Means for extinguishing an arc which may occur between spaced terminals comprising a container of insulating material, closure members at the ends of the container, the outer closure member being of conducting material and secured to one of the terminals, the inner closure member being of fusible material, a fusible conductor extending through the container and projecting beyond the inner end thereof, said conductor being connected to the outer closure member, and arc extinguishing material within the container surrounding said conductor.

4. Means for extinguishing an aro which may occur between spaced terminals comprising a fusible conductor connected to one of the terminals and extending toward the other terminal, a plurality of sealed containers of insulating material mounted upon the conductor, and arc extinguishing material in the respective containers surrounding said conductor.

5. Means for extinguishing an arc which may occur between spaced terminalscomprising a container of insulating material provided at its outer end with a closure member of conducting material secured to one of the terminals, the inner end of the container being closed by a fusible member, a fusible conductor connected to the outer closure member and extending through the container and beyond the inner end thereof, additional containers of insulating material and having fusible end closure members mounted on the ,inner portion of the conductor, and arc exfusible conductor connected to the outer closure member and extending through the container and beyond the inner end thereof, additional containers of insulating material and having fusible and closure members mounted on the inner portion of the conductor, and arc extinguishing material in the respective containers surrounding the conductor, the conductor projecting beyond the innermost container toward the other arcing terminal.

7. A device for extinguishing an arc which may occur between spaced terminals, comprising a container of insulating material carried by one terminal, conducting closure means for one end of the container connected with said terminal, a ,fusible metal closure for the other end, a fusible conductor connected to said first named closure means and extending through and projecting beyond the second named closure, and fire extinguishing material located within the container.

8.' Means for extinguishing an arc which may occur between spaced terminals, comprisinga supporting member of conducting material mounted upon one terminal, a container of insulating material carried and closed at one end by said supporting member and having a closure for its other end, a fusible conductor electrically and mechanically connected with said supporting member and extending through the container and projecting beyond said closure, a filling of fire extinguishing material Within the container surrounding said conductor, and means adapted to become discolored or destroyed in the event of an arc.

9. Means for extinguishing an arc which may occur between spaced terminals, comprising a supporting member of conducting material mounted upon one terminal, a container of insulating material carried by said supporting member and having end closures, a fusible conductor electrically and mechanically connected With said supporting member and extending through and projecting beyond the container, a filling of fire extinguishing material Within the container surrounding said conductor, and means at one end adapted to become discolored or destroyed in the event of an arc, said means comprising a paper disk through which the conductor extends.

l0. Means for extinguishing an arc which may occur between spaced terminals, comprising a metallic supporting member mounted on one terminal, a conductor secured to said supporting member, a series of containers arranged in end to end relation with said conductor extending through all thereof and projecting beyond the endmost one, end closures for each separate container, and a filling of lire extinguishing material within each container.

f 11. Means for extinguishing an arc or series of arcs which may occur between spaced terminals, comprising a conductor carried by and electrically connected with one terminal and extending toward the other, and a plurality of individual containers of insulating material provided with closure means an filled with fire extinguishing material mounted upon the conductor with the con.

ductor extending through all and projecting beyond the endmost one.

In witness whereof, I hereunto subscribe my name this 23rd day of December, 1926.

ALEXANDER M. JACKSON. 

